Armstrong Whitworth Whitley

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Armstrong Whitworth A.W.38 Whitley

Type	Medium bomber
Manufacturer	Armstrong Whitworth Aircraft
Maiden flight	1936-03-17
Introduced	1937
Retired	1942
Primary user	Royal Air Force
Number built	1,737

The Armstrong Whitworth A.W.38 Whitley was one of three twin-engine, front-line medium bomber types in service with the Royal Air Force at the outbreak of World War II. It was produced by Armstrong Whitworth Aircraft.

1 Development
2 Operational history
3 Variants
4 Operators
5 Units using the Whitley
6 Civil Operators
7 Specifications (Mk V)
8 References
9 External links
10 Related content

[edit] Development

The Whitley was developed by John Lloyd, the chief designer of Armstrong Whitworth Aircraft from the Armstrong Whitworth AW.23 bomber-transport to meet Air Ministry Specification B.3/34 for a heavy night bomber. While the AW.23 was a low wing monoplane, the Whitley had a mid wing and a monocoque fuselage with slab sides to ease production. As Lloyd was unfamiliar with the use of flaps on a large heavy monoplane, the wings were set at a high angle of incidence to give good take off and landing performance. As a result, all Whitleys flew with a pronounced nose-down attitude of the fuselage ^[1]. This 'nose down' attitude was first seen in the design of the Armstrong-Whitworth Ensign pre-war airliner.

The first prototype Whitley first flew on March 17, 1936, powered by two 795 hp Armstrong Siddeley Tiger IX engines ^[2]. Owing to the urgent need to replace biplane heavy bombers still in service with the RAF, an order for 160 aircraft had been placed in 1935, before the Whitley had first flown. After the first 34 aircraft had been built, the engines were replaced with more reliable Tiger VIIIs, in the Whitley II.

While the Tiger VIIIs used in the Whitley II and III were more reliable than those used in early aircraft, in 1938, the Whitley was re-engined with Rolls Royce Merlin engines, giving rise to the Whitley IV.

Early marks of the Whitley had bomb bay doors which were kept closed by bungee cords, and opened by the weight of the released bombs falling on them. The Mk III version introduced hydraulically actuated doors which greatly improved bombing accuracy. To aim bombs, the bombardier had to open a hatch in the nose of the aeroplane which extended the bomb sight out of the fuselage, but to everyone's comfort, the Mk IV replaced this hatch with a slightly extended transparency.

A total of 1,737 Whitleys were produced.

[edit] Operational history

The Whitley first entered service with No. 10 Squadron in March, 1937 ^[2], replacing Handley Page Heyford biplanes.

By the outbreak of World War II, seven squadrons were operational with the Whitley, with the majority flying Whitley IIIs or IVs, with the Whitley V having just been introduced^[2] ^[3].

Along with the Handley Page Hampden and the Vickers Wellington, it bore the brunt of the early fighting, seeing action on the first night of the war, dropping leaflets over Germany. Amongst the many aircrew who flew the Whitley in operations over Germany was the later to be famous Leonard Cheshire who spent most of his first three years at war flying Whitleys. Unlike the Hampden and Wellington, however, the Whitley was always intended for night operations, and so did not share the early heavy losses received in attempted daylight raids on German shipping early in the war. Along with Hampdens, the Whitley made the first raid on German soil, dropping bombs on the night of March 19-20, 1940. Whitleys also carried out the first RAF raid to Italy in June, 1940.

As the oldest of the three bombers, the Whitley was obsolete by the start of the war yet over 1,000 more were produced before a suitable replacement was found. The Whitley was retired from all front-line service in late 1942 but it continued to operate as a transport for troops and freight (including service with BOAC) as well as towing gliders. No. 100 Group RAF used Whitleys to carry airborne radar and counter-measures.

With Bomber Command Whitleys flew 8,996 operations, dropped 9,845 tons of bombs and lost 269 aircraft in action.

BOAC operated 15 Whitley 5s converted into freighters in 1942. These were needed to run night supply flights from Gibraltar to Malta. They took seven hours to reach the island, often landing during air attacks. They proved to use large quantities of fuel for a small payload and were replaced in August 1942 by the Lockheed Hudson ^[4]. The 14 survivors were returned to the Royal Air Force.

[edit] Variants

Thirty-four of the Mk I and 46 Mk II Whitleys were built, powered by two 795 hp Armstrong Siddeley Tiger IX radial engines. The 80 Mk III aircraft received the 920 hp Tiger VIII engine and a retractable ventral turret aft of the wing root. In 1938 the powerplant was altered to use the Rolls Royce Merlin inline liquid-cooled engine, resulting in 33 Mk IV aircraft powered by the 1,030 hp Merlin IV and seven Mk IVA being produced using the 1,145 hp Merlin X.

At the outbreak of the war the RAF had 207 Whitleys in service, ranging from Mk I to Mk IV types. The Mk IV became the basis for the main wartime production mark, the Mk V, which first flew in December 1938. Powered by the Merlin X, the Mk V had a longer fuselage and a modified tail. A total of 1,466 were built before production ceased in June 1943. The Mk VI was intended to be fitted with Pratt & Whitney engines, but none were ever built.

The final Whitley variant was the Mk VII, designed for service with Coastal Command. The Mk VII was capable of longer range flights and equipped with an ASV radar for anti-shipping patrols. A Mk VII Whitley achieved the first Coastal Command sinking of a German U-boat, the U-206, in November 1941.

[edit] Operators

United Kingdom
- Royal Air Force

[edit] Units using the Whitley

No. 7 Squadron RAF
No. 10 Squadron RAF
No. 51 Squadron RAF
No. 53 Squadron RAF
No. 58 Squadron RAF
No. 77 Squadron RAF
No. 78 Squadron RAF
No. 97 Squadron RAF
No. 102 Squadron RAF
No. 109 Squadron RAF
No. 166 Squadron RAF
No. 295 Squadron RAF
No. 296 Squadron RAF
No. 297 Squadron RAF
No. 298 Squadron RAF
No. 502 Squadron RAF
No. 612 Squadron RAF

[edit] Civil Operators

BOAC.

[edit] Specifications (Mk V)

General characteristics

Crew: 5
Length: 70 ft 6 in (21.49 m)
Wingspan: 84 ft (25.60 m)
Height: 15 ft (4.57 m)
Wing area: 1,137 ft² (106 m²)
Empty weight: 19,300 lb (8,768 kg)
Max takeoff weight: 33,500 lb (15,196 kg)
Powerplant: 2× Rolls-Royce Merlin X liquid-cooled V12 engine, 1,145 hp (855 kW) each

Performance

Maximum speed: 200 knots (230 mph, 370 km/h) at 16,400 ft (5,000 m)
Combat radius: 1,430 nm (1,650 mi, 2,650 km)
Ferry range: 2,100 nm (2,400 mi, 3,900 km)
Service ceiling: 26,000 ft (7,900 m)
Rate of climb: 800 ft/min (4.1 m/s)
Max wing loading: 29.5 lb/ft² (143 kg/m²)
Minimum power/mass: 0.684 hp/lb (112 W/kg)

Armament

Guns:
- 1× .303 in (7.7 mm) Vickers machine gun in nose turret
- 4× .303 Browning machine guns in tail turret
Bombs: Up to 7,000 lb (3,200 kg) of bombs in the fuselage and 14 individual cells in the wings, typically including
- 12× 250 lb (110 kg) and
- 2× 500 lb (230 kg) bombs
- Bombs as big as 2,000 lb (907 kg) could be carried

[edit] References

^ Gunston, B. (1995). Classic World War II Aircraft Cutaways. Osprey. ISBN 1-85532-526-8.
^ ^a ^b ^c Mason, Francis K (1994). The British Bomber since 1914. Putnam Aeronautical Books. ISBN 0 85177 861 5.
^ Thetford, Owen (1957). Aircraft of the Royal Aircraft 1918-57. Putnam & Co.
^ Jackson, A.J. (1973). British Civil Aircraft since 1919 (Volume 1). Putnam. ISBN 0-370-10006-9.

Donald, D.; Lake, J. (1996). Encyclopedia of world military aircraft. AIRtime Publishing. ISBN 1-880588-24-2.
Cheshire, L. (1943). Bomber Pilot. Goodall. ISBN 0-907579-10-8.